• Title/Summary/Keyword: Nam Byung Gil

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A Study on Correlations between Compaction Properties and Soil Constants of Granite Soil in the Kangwon Province (강원도에 분포하는 화강토의 다짐특성 및 토질정수의 상관관계에 관한 연구)

  • Yoo, Nam-Jae;Park, Byung-Soo;Hong, Young-Gil
    • Journal of Industrial Technology
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    • v.18
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    • pp.77-86
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    • 1998
  • This study is to provide the useful data for the design and construction of the geotechnical engineering works by collecting and analyzing the soil properties of granite soil in the Kangwon Province. Data base was obtained from 92 field sites in the Kangwon province divided into 15 areas based on administration district. Total numbers of data were 478. Correlations between soil constants, especially compaction properties, were obtained by performing statistical analysis. Analyzed results were as follows. 1. Most of granite soil consists of SM and GM based on United Soil Classification System. 2. Mean gravity of granite soil is 2.65 3. High correlations between optimum moisture content and the maximum dry density, plasticity index and liquid limit are obtained. 4. Analyzed results between other soil constants show relatively low correlation. However, they show consistent trends matchable to geotechnical engineering senses.

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A Study on the Control of Single Phase Induction Motor by Full Bridge Series Inverter (직렬 브리지형 인버터에 의한 단상 유도전동기의 속도제어)

  • Park, Jin-Gil;Roh, Young-O;Jung, Byung-Gun;Kang, Chang-Nam;Jung, Sam-Sig
    • Proceedings of the KIEE Conference
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    • 1993.07b
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    • pp.912-915
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    • 1993
  • In this paper, the speed of single phase induction motor driven by full bridge inverter is controlled by a PID controller under condition of disturbance load and setpoint changes, and the current characteristics of the system is investigated to look for the good properties of A.C. motor torque through the results of experiment. From the experimental result, it is confirmed that the speed of single phase induction motor driven by full bridge series inverter can be smoothly controlled by an analog PID controller.

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Molecular and Biochemical Characteristics of ${\beta}$-Propeller Phytase from Marine Pseudomonas sp. BS10-3 and Its Potential Application for Animal Feed Additives

  • Nam, Seung-Jeung;Kim, Young-Ok;Ko, Tea-Kyung;Kang, Jin-Ku;Chun, Kwang-Hoon;Auh, Joong-Hyuck;Lee, Chul-Soon;Lee, In-Kyu;Park, Sunghoon;Oh, Byung-Chul
    • Journal of Microbiology and Biotechnology
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    • v.24 no.10
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    • pp.1413-1420
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    • 2014
  • Phytate is an antinutritional factor that impacts the bioavailability of essential minerals such as $Ca^{2+}$, $Mg^{2+}$, $Mn^{2+}$, $Zn^{2+}$, and $Fe^{2+}$ by forming insoluble mineral-phytate salts. These insoluble mineral-phytate salts are hydrolyzed rarely by monogastric animals, because they lack the hydrolyzing phytases and thus excrete the majority of them. The ${\beta}$-propeller phytases (BPPs) hydrolyze these insoluble mineral-phytate salts efficiently. In this study, we cloned a novel BPP gene from a marine Pseudomonas sp. This Pseudomonas BPP gene (PsBPP) had low sequence identity with other known phytases and contained an extra internal repeat domain (residues 24-279) and a typical BPP domain (residues 280-634) at the C-terminus. Structure-based sequence alignment suggested that the N-terminal repeat domain did not possess the active-site residues, whereas the C-terminal BPP domain contained multiple calcium-binding sites, which provide a favorable electrostatic environment for substrate binding and catalytic activity. Thus, we overexpressed the BPP domain from Pseudomonas sp. to potentially hydrolyze insoluble mineral-phytate salts. Purified recombinant PsBPP required $Ca^{2+}$ or $Fe^{2+}$ for phytase activity, indicating that PsBPP hydrolyzes insoluble $Fe^{2+}$-phytate or $Ca^{2+}$-phytate salts. The optimal temperature and pH for the hydrolysis of $Ca^{2+}$-phytate by PsBPP were $50^{\circ}C$ and 6.0, respectively. Biochemical and kinetic studies clearly showed that PsBPP efficiently hydrolyzed $Ca^{2+}$-phytate salts and yielded myo-inositol 2,4,6-trisphosphate and three phosphate groups as final products. Finally, we showed that PsBPP was highly effective for hydrolyzing rice bran with high phytate content. Taken together, our results suggest that PsBPP has great potential in the animal feed industry for reducing phytates.

Research and Development of High Performance 50-inch HD Plasma Display Panel

  • Choi, Kwang-Yeol;Min, Woong-Kee;Rhee, Byung-Joon;Ahn, Byung-Nam;Kim, Je-Seok;Moon, Won-Seok;Park, Min-Soo;Ryu, Byung-Gil;Kim, Sung-Tae;Ahn, Young-Joon;Yang, Sung-Soo;Kim, Kyung-Tae;Lee, Kyu-Sung
    • 한국정보디스플레이학회:학술대회논문집
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    • 2008.10a
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    • pp.1547-1550
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    • 2008
  • We are suggesting a new index to represent the performance of PDP, such as Specific Performance Index (SPI) that includes luminous efficacy and panel reflectance. High Xe gas mixture and low panel capacitance are well known as key factors to improve luminous efficacy of PDP [1]. However, higher driving voltage and longer discharge time lag is an obstacle when applying these technologies. Modified cell design, new materials and driving waveform enable us to overcome these obstacles. High efficient phosphor is also a key material to improve luminous efficacy. Phosphors coated with pigment are used to reduce panel reflectance. High performance 50-inch HD PDP with luminous efficacy of 2.3 lm/W has been developed.

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Application of a Gas Chromatography/Mass Spectrometric Method for the Determination of Butyltin Compounds in Sediment

  • Won, Yong-Il;Jung, Pyong-Gil;Chung, Min-Young;Kim, Byung-Joo;Yim, Yong-Heon;So, Hun-Young;Kim, Yong-Seong
    • Bulletin of the Korean Chemical Society
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    • v.25 no.10
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    • pp.1508-1512
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    • 2004
  • A gas chromatography/mass spectrometric (GC/MS) method has been developed for the determination of trace mono-n-butyltin (MBT), di-n-butyltin (DBT), and tri-n-butyltin (TBT) compounds in sediments. Samples were extracted by 10% acetic acid in methanol containing 0.03% tropolone and were then derivatized for GC/MS analysis. Ethylation by sodium tetraethylborate and phenylation by sodium tetraphenylborate were evaluated as a derivatization reaction of the organotins in sample extract. n-Hexane was added into reaction media in the beginning of the reaction for the continuous extraction of derivatized organotins. Ethylation requires less than 2 hours to get proper derivatization yields for MBT, DBT, and TBT altogether and produces relatively low amounts of side reaction products. Compared to ethylation, phenylation requires much longer time but provides relatively lower yield and produces considerable amounts of side reaction products. Therefore, the ethylation reaction was applied for the analysis of organotin compounds in sediment. An isotope dilution mass spectrometric (IDMS) method based on GC/MS has been applied to the accurate determination of DBT compounds in the sediments. The IDMS results from the analyses of sediment samples showed a reasonable repeatability and a good agreement with the values obtained by IDMS based on liquid chromatography/induced coupled plasma/mass spectrometry.

The Clinical and Histopathologic Findings of Lymphonodular Hyperplasia of the Colon in Infancy and Childhood (소아에서 대장 림프결절증식의 임상적 및 병리조직학적 소견)

  • Nam, Yoo-Nee;Lee, Seung-Hyeon;Chung, Dong-Hae;Sim, So-Yeon;Eun, Byung-Wook;Choi, Deok-Young;Sun, Yong-Han;Cho, Kang-Ho;Ryoo, Eell;Son, Dong-Woo;Jeon, In-Sang;Tchah, Hann
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.12 no.1
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    • pp.1-9
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    • 2009
  • Purpose: Lymphonodular hyperplasia of the colon (LNHC) is a rare finding in children and its significance as a pathologic finding is unclear. The aim of this study was to investigate the clinical significance of LNHC by analyzing clinical and histopathologic findings in children with LNHC. Methods: We analyzed data from 38 patients who were confirmed to have LNHC by colonoscopy. We checked age, birth history, past history, family history, and clinical symptoms. A hematologic exam, stool exam, and image studies were performed and biopsy specimens were examined by a pathologist. All patients were asked to have short- and long-term follow-up. Results: The mean age of the patients was 12.5${\pm}$14.4 months. All patients presented with complaints of bloody stool. They appeared healthy and the hematologic findings were within a normal range, with the exception of one case. There was no other identified source of bleeding. On histologic exam, 36 patients (94.7%) had lymphoid follicles and 34 patients (84.5%) fulfilled the criteria of allergic colitis. Regardless of diet modification and presence of residual symptom, there was no recurrence of bloody stool through long-term follow-up in all patients. Conclusion: LNHC is more common in infants who are affected by allergic colitis, but it can appear even after infancy. LNHC should be regarded as the etiology when there are any other causes of rectal bleeding, especially in healthy children. We suggest that LNHC has a benign course regardless of diet modification and it might not require excessive concerns.

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Stomach clusterin as a gut-derived feeding regulator

  • Cherl NamKoong;Bohye Kim;Ji Hee Yu;Byung Soo Youn;Hanbin Kim;Evonne Kim;So Young Gil;Gil Myoung Kang;Chan Hee Lee;Young-Bum Kim;Kyeong-Han Park;Min-Seon Kim;Obin Kwon
    • BMB Reports
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    • v.57 no.3
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    • pp.149-154
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    • 2024
  • The stomach has emerged as a crucial endocrine organ in the regulation of feeding since the discovery of ghrelin. Gut-derived hormones, such as ghrelin and cholecystokinin, can act through the vagus nerve. We previously reported the satiety effect of hypothalamic clusterin, but the impact of peripheral clusterin remains unknown. In this study, we administered clusterin intraperitoneally to mice and observed its ability to suppress fasting-driven food intake. Interestingly, we found its synergism with cholecystokinin and antagonism with ghrelin. These effects were accompanied by increased c-fos immunoreactivity in nucleus tractus solitarius, area postrema, and hypothalamic paraventricular nucleus. Notably, truncal vagotomy abolished this response. The stomach expressed clusterin at high levels among the organs, and gastric clusterin was detected in specific enteroendocrine cells and the submucosal plexus. Gastric clusterin expression decreased after fasting but recovered after 2 hours of refeeding. Furthermore, we confirmed that stomachspecific overexpression of clusterin reduced food intake after overnight fasting. These results suggest that gastric clusterin may function as a gut-derived peptide involved in the regulation of feeding through the gut-brain axis.

The Behavior of Shallow Foundation under Eccentric Loads by Centrifuge Model Experiment (원심모형시험에 의한 편심하중을 받는 얕은기초의 거동)

  • Yoo, Nam-Jae;Lee, Myung-Woog;Park, Byung-Soo;Jeong, Gil-Soo
    • Journal of Industrial Technology
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    • v.22 no.A
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    • pp.229-240
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    • 2002
  • This paper is an experimental and numerical work of Investigating the bearing capacity of shallow foundation of rubble mound under eccentric loads. Parametric centrifuge model tests at the 50g level environments with the model footings in the form of strip footing were performed by changing the loading location of model footing, relative density and materials for ground foundation. For the model ground, crushed rock sampled from a rocky mountain was prepared with a grain size distribution of having an identical coefficient of uniformity to the field condition. Model ground was also prepared with relative densities of 50 % and 80 %. For loading condition, model tests with and without eccentric load were carned out to investigate the effect of eccentric loads and a numerical analysis with the commertially available software of FLAC was performed. For numerical estimation with FLAC, the hyperbolic model of a nonlinear elastic constitutive relationship was used to simulate the stress-stram constitutive relationship of model ground and a series of triaxial compression test were carried out to find the parameters for this model Test results were analyzed and compared with Meyerhof method (1963), effective area method based on the limit equilibrium method, and a numerical analysis with FLAC.

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Stress Concentration Characteristics of Soft Ground Treated by Sand Compaction Pile (모래다짐말뚝으로 개량된 연약지반의 응력분담특성)

  • Yoo, Nam-Jae;Park, Byung-Soo;Jeong, Gil-Soo;Kim, Sang-Jin
    • Journal of Industrial Technology
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    • v.22 no.A
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    • pp.145-151
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    • 2002
  • This paper is results of extensive centrifuge model experiments about design factors influencing the bearing capacity and the settlement behaviors of SCP (Sand Compaction Pile). Centrifuge model tests were carried out changing design factors for SCP method such as replacement area ratio (as= 20, 40, 70%), Improvement ratio to footing width (W/B = 1, 2, 3), and amount of fines m sand pile (#200 = 5, 10, 15). Therefore, the effects of these design factors on the bearing capacity and the settlement behavior of SCP were investigated and changes of stress concentratio rato due to such an design factors were also investigated. Centrifuge model testing technique for preparing and installing centrifuge model of sand compaction pile, using freezing them, was also developed. As results of centrifuge model tests, more fines in sand compaction pile increases the bearing capacity of SCP. Optimum improvement ratio to footing width was found to be 2. Values of stress concentration ratio was in the ranges of 1.5 - 3.5. The depth of bulging in sand plies was found in the range of 2.0 - 2.5 times of pile diameter.

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Characteristics of Anchor Behavior Resisting Buoyancy Forces in the Weathered Rock (풍화암에 시공된 부력저항 앵커의 거동특성)

  • Yoo, Nam-Jae;Lee, Gun-Chag;Jeong, Gil-Soo;Park, Byung-Soo
    • Proceedings of the Korean Geotechical Society Conference
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    • 2005.10a
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    • pp.698-705
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    • 2005
  • This study contains actual scaled site experiments on mediation factors affecting ultimate pulling force of the buoyancy resisting anchor which is installed underground water level suffering buoyancy force and breaking mechanism. Site buoyancy test selected the buoyancy acting site where acting buoyancy to the station structure since the stream and reservoir is neighboured to the vicinity ground and executed site experiments leading to variation of anchoring length, drilling diameter and tendon diameter at the weathered rock ground. The test result showed that pulling force getting increased more and more proportionate to increase of anchoring length, drilling diameter and tendon diameter, and as a result of analysis for correlations between anchoring length-ultimate limited load and drilling diameter-ultimate load (on the basis of 254mm settlement), modulus of correlation showed very high relation 0.9 and 0.99 respectively and correlation formular showed the limited load is increasing proportionate to cubic meters of anchoring length as well as the ultimate load proportionate to alignment of drilling diameter. It is also showed that limited load increased about 42.5% from 392kN to 559kN as a result of change the tendon diameter to 36mm and 50mm.

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